Users guide

Intel® RAID Software User Guide 24
2.4.4 Drive in Foreign State
When newly inserted drives are detected by the RAID controller, and are displayed in
either RAID BIOS Console 2 or RAID Web Console 2, their state may show as (Foreign)
Unconfigured Good, or (Foreign) Unconfigured Bad. The Foreign state indicates that the
RAID controller finds existing RAID configuration on the new drives. Since these drives
cannot be configured directly, avoid deleting data on the existing RAID by mistake. Use
“Scan for Foreign Configuration” option in RAID Web Console 2, or use “Scan Devices”
option in RAID BIOS Console 2, in order to preview, import or clear the existing RAID
configurations on the drives. If existing RAID configurations are cleared, their state
changes to Unconfigured Good or Unconfigured Bad.
2.4.5 Copyback
The copyback feature allows you to copy data from a source drive of a virtual drive to a
destination drive that is not a part of the virtual drive. Copyback is often used to create or
restore a specific physical configuration for a drive group (for example, a specific
arrangement of drive group members on the device I/O buses). Copyback can be run
automatically or manually.
Typically, when a drive fails or is expected to fail, the data is rebuilt on a hot spare. The
failed drive is replaced with a new disk. Then the data is copied from the hot spare to the
new drive, and the hot spare reverts from a rebuild drive to its original hot spare status.
The copyback operation runs as a background activity, and the virtual drive is still
available online to the host.
Copyback is also initiated when the first Self-Monitoring Analysis and Reporting
Technology (SMART) error occurs on a drive that is part of a virtual drive. The
destination drive is a hot spare that qualifies as a rebuild drive. The drive with the SMART
error is marked as "failed" only after the successful completion of the copyback. This
avoids putting the drive group in degraded status.
Note: Du
ring a copyback operation, if the drive group involved in the copyback is deleted
because of a virtual drive deletion, the destination drive reverts to an Unconfigured Good
state or hot spare state.
2.4.5.1 Order of Precedence
In the following scenarios, rebuild takes precedence over the copyback operation:
1. If a copyback operation is already taking plac
e to a hot spare drive, and any virtual
drive on the controller degrades, the copyback operation aborts, and a rebuild starts.
The rebuild changes the virtual drive to the optimal state.
2. The rebuild operation takes precedence ove
r the copyback operation when the
conditions exist to start both operations. For example:
— Where the hot spare is not configured (or unavailable) in the
system.
— There are two drives (both members of virtual drives), with one drive
exc
eeding the SMART error threshold, and the other failed.